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Finding the Fourth Proportional to 420.63, 630.38 and 305.46

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Solution

The fourth proportional to 420.63, 630.38 and 305.46 is: 457.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.63 : 630.38 = 305.46 : x
  2. Step 2: Convert to fraction form
    420.63/630.38 = 305.46/x
  3. Step 3: Cross multiply
    420.63x = 630.38 × 305.46
  4. Step 4: Simplify right side
    420.63x = 192,554.35
  5. Step 5: Solve for x
    x = 192,554.35/420.63
  6. Step 6: Final answer
    x = 457.78

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.